Overview of the Windows NT Architecture

In this short section of the chapter, we'll present a brief overview of the Windows NT architecture, pointing out and illustrating the major concepts and organization. Later sections in the chapter will drill into the details beneath the major topics introduced here.

Understanding Multiprocessing and Threads

As you learned in Chapter 1, "Understanding Windows NT Workstation 4.0," Windows NT truly lets you do more than one task at one time via a preemptive multitasking scheme. To illustrate, here is a point of comparison. In Windows 3.x and Windows 95, applications cooperatively release control of the CPU to other applications. In Windows NT, CPU manages its own time. The CPU pays attention to applications as it sees fit and according to the priorities defined by the system administrator. These applications are known as processes. A process can be your word processing application, a print job, or the system reading from a file on disk. In Windows NT, each of the processes can run at the same time. The amount of memory on your system determines how efficiently processes run, as well as how many processes can run efficiently at one time.